Gandak navigation: Past and future prospects

Complete disruption to navigation on the Gandak River is anticipated in the wake of full capacity operation of the Gandak Irrigation Project that is established as per the Gandak River Treaty, 1959 signed between Nepal and India.

The Gandak River was navigable by country crafts from the time immemorial. It provided principle means of communication in the areas traversed by it. The Joint Steamer Company providing navigation services on the Ganges had even conducted a survey during the last years of the British rule with the view to extend their services on the Gandak River.

The River Gandak after passing through Deoghat flows down in a succession of rapids and pools until it reaches Tribeni. Passing Tribeni, the river traverses a distance of about 310 km before it empties into the Ganges at Hajipur, opposite Patna.

At one point, even the provincial government of Bihar had considered making one of the two Gandak main irrigation canals navigable as an alternative to the river course navigation. Obviously, this is now the only recourse to save the Gandak navigation unless both countries agree to take drastic measure to do away with the Gandak Treaty.

Physical features

The River Gandak after passing through Deoghat flows down in a succession of rapids and pools until it reaches Tribeni. Passing Tribeni, the river traverses a distance of about 310 km before it empties into the Ganges at Hajipur, opposite Patna.

The Gandak River becomes much wider after debouching into the plains at Tribeni, where it acquires the characteristics of a deltaic river. Except for four rapids at Damran, Narasahi, Thari, and Patlahwa between Tribeni and Bagaha where there are boulders and shingle, the river bed in most of its course down Tribeni is sandy.

Pre-Gandak project status

The Gandak River had always been navigable throughout the years by country boats from the confluence at the Ganges up to the Tribeni in Nepal.  It was a very important channel of trade of this area even in the early days of the British rule and the transportation via this river can be traced back to 1700 AD.

The volume of water flow on Tribeni-Bagaha sector, excluding the appreciable quantities of boulders and shingles, picked up from the river bed, according to NCAER study aggregates to about 20,000 tons. Boats up to 15 tons capacity can ply in this section.

From the viewpoint of navigation, the Gandak waterway can be divided into the following four sections. Deoghat-Tribeni Section (78 km), Tribeni-Bagaha Section (50 km), Bagha-Mallahi Section, Mallahi-Confluence.

A study conducted by the National Council of Applied Economic Research (NCAER) in 1963 indicates that the total annual water flows at that time at Tribeni and upstream from Tribeni was about 20,000 tons. At such state, the river is navigable for about eight months in a year. Boats of only two tons capacity can ply under the given amount of water flow in the river.

The volume of water flow on Tribeni-Bagaha sector, excluding the appreciable quantities of boulders and shingles, picked up from the river bed, according to NCAER study aggregates to about 20,000 tons. Boats up to 15 tons capacity can ply in this section.

Country crafts up to 20 tons capacity used to ply on Bagaha-Mallahi section once.

However, nothing concrete came out of those surveys. The service on the Gandak had always been by country crafts, provided by a large number of boat-owners and boatmen from Patna without any coordination with the Joint Steamer Company’s services. It should be noted that Nepal too had conducted a survey of the river with the support of UNDP in 1967.

The volume of water flow on Mallahi confluence section according to NCAER study was about 40,000 tons. Country crafts with a capacity of 20 tons or more used to ply on this section of the river. However, all the boats up and down the river had to stop for some time near the railway bridge at Hajipur for lowering and raising their masts and sails.

Joint steamer companies’ surveys

Until the advent of the railways and road transport, the Gandak supplied the principal means of communication in the area traversed by it. In spite of the introduction of an alternative mode of surface transportation, sizeable traffic continued to exist on the Gandak River. So the Government of India had shown considerable interest in developing Gandak waterway for navigation in the past.

The Joint Steamer Companies operating on the Ganges were providing services for a very long time before the complete closure of such services in the 1950s. They were operating feeder services on the lower reaches of the Karnali River (known as Gogra in India) also.  However, there was no feeder service on the Gandak to link with the Joint Steamer Navigation Services on the Ganges. They had carried out surveys on the Gandak River during 1935, 1941 and 1946 with a view of extending their services on the Gandak up to Sohansi Ghat. The surveys studied the level of water flow or water capacity of the river in various months of a year. They also mentioned about the depth of the water along with various stretches and the possibility of operating water vessels at various sections of the river.

However, nothing concrete came out of those surveys. The service on the Gandak had always been by country crafts, provided by a large number of boat-owners and boatmen from Patna without any coordination with the Joint Steamer Company’s services. It should be noted that Nepal too had conducted a survey of the river with the support of UNDP in 1967.

The main objective of the study was to find out the possibility of developing water transport from the nearest port to terminal points inside Nepal. All three major rivers the Karnali, the Gandak and the Koshi were investigated. The study team recommended giving priority to the Gandak River for early development because at that time the Gandak River had sufficient water for developing water transportation and this river was found favorable for effectively serving the whole country.

Impediments to navigation

There are many old and new railway bridges with low clearance above the high-water level at Hajipur. They are serious impediments to navigation development on the Gandak River. But of all such impediments, the Gandak Project at Bhaisalotten is the most serious and it can preclude the possibility of developing navigation on the Gandak.

An agreement between the government of Nepal and the government of India on Gandak Project was signed on December 4, 1959. This agreement has been amended and the revised agreement was signed on April 30, 1964. The Gandak Project comprises of a barrage and the canals for irrigation and power generation.

An 835 m long barrage is built across the Gandak River at Bhaisaloten. About half the length of the barrage is in Nepal and the other half is in Indian territory. The barrage blocks the waterway and thus the navigation. But according to the Gandak agreement the government of India would have to provide locking arrangements for facilitating the riverine traffic across the barrage free from payment of any tolls. India had proposed to provide a lock with a width of only 6.1 meters. The UNDP supported Nepal’s study had pointed out that the lock width should at least be 15.25 meters.

Thus, this waterway would herald a completely new era of development by facilitating trade and industrialization in North-West Bihar, Eastern UP, and Western Nepal.

There are two main canals in the barrage. They are the main western canal and main eastern canal with the head discharge of 15,000 cusecs and 14,140 cusecs respectively primarily for irrigation purposes.

A large volume of water is required to irrigate lands within the total catchment area of the Gandak Project. During the rainy season, the water demand for irrigation will not be heavy. The demand increases in the dry season. The river shrinks in the dry season as its water is channeled to irrigation canals. In this context, the question of the continuity of navigation becomes crucial. If this problem is not resolved then the navigation would not only become difficult but would be precluded forever.

Possible solution

Conversion of one of the two main Gandak canals into an irrigation cum navigation canal (including power generation component if feasible) is the only recourse to save the Gandak navigation. The proposed modification could open a relatively deep waterway route for vessels on a par with the Patna-Faracca sector Ganges waterway, which would significantly contribute to reducing the transportation cost. Thus, this waterway would herald a completely new era of development by facilitating trade and industrialization in North-West Bihar, Eastern UP, and Western Nepal.